Aiming arm for bone plates

ABSTRACT

An aiming guide aligns a surgical tool with a hole in a bone plate. The aiming guide includes an arm portion having a longitudinal axis, top and bottom surfaces, and first and second ends. The aiming guide further includes a handle portion having upper and lower ends. The handle portion is, at its lower end, connected to the bone plate. The handle portion is, at its upper end, connected to the arm portion. Bores extend from the top surface to the lower surface of the arm portion. Each bore is configured and dimensioned to receive a tool guide in at least two different preset positions which locates the channel in at least two different hole positions. The bore includes two diametrically opposed slots extending along at least a portion of a length of the bore, the slots configured and dimensioned to mate with diametrically opposed knobs extending radially outward from a tool guide. The tool guide has a head and a sleeve portion, which has a centered channel. The sleeve portion and channel are eccentric with respect to the head portion. The tool guide is inserted in a first preset position in order to align a surgical tool with one portion of a two-portion bone plate hole, or in a second preset position rotated 180° from the first preset position, in order to align a surgical tool with the second portion of a two-portion bone plate hole.

FIELD OF THE INVENTION

The present invention relates to an apparatus for aligning surgicaltools (e.g., drill bit, trochar) with a hole in bone plate.

BACKGROUND OF THE INVENTION

Surgical devices which align tools (e.g., drill bits, trochars) to boneplate holes are known in the art. Many of these devices are notadjustable. Some of these known devices can be adjusted by the surgeonor operator to tailor it for use with a number of different bone plateswhich have varying hole placement arrangements or patterns. Theseadjustable devices, however, require the surgeon or operator to manuallyadjust the guide to suit the particular plate being used. Making theseadjustments can be tedious and often requires trial and error.Furthermore, even after a surgeon adjusts one of these devices, thealignment between the guide and a respective plate hole may beimprecise. These problems become even more salient when the device beingused is intended to align a tool (e.g., a drill bit) with so-called boneplate “combination holes.” Indeed, it appears that no existing alignmentdevice is designed for, or even particularly compatible with, a platethat has combination holes. A “combination hole,” as used here, meansany kind of hole in which there are multiple “hole positions” any one ofwhich a surgeon can drill or operate through. For an example, see thecombination holes disclosed in U.S. Pat. No. 6,669,701 and thecombination holes disclosed in U.S. Pat. No. 6,719,759, thespecifications of which are hereby incorporated by reference.

There thus exists a need for a device that will align a surgical tool(e.g., drill bit) with a bone plate hole or that can be “adjusted” oraligned with a bone plate hole or a portion of a bone plate hole withminimal effort and maximum precision. This need is especially evidentwhen a bone plate having combination holes is used. The presentinvention addresses this problem and others by providing an aiming armwhich has aligning bores, whose arrangement matches or corresponds tothe arrangement of holes of a particular bone plate type. Whenadjustment is needed, for example when a bone plate that has combinationholes is being used, the present invention may provide an aiming armthat has guide bores, each guide bore having multiple (i.e., at least 2)preset positions in which to introduce or position a guide sleeve, eachposition providing for alignment with a particular, different holeportion. Because the positions are preset, maneuvering each guide sleeveto the desired position is very easy and takes a very short amount oftime.

SUMMARY OF THE INVENTION

The aiming guide system of the present invention provides alignmentbetween a surgical tool (e.g., a drill bit, a trochar) and holes or holeportions in a bone plate.

The aiming guide system may be used with a bone plate having virtuallyany hole distribution arrangement and virtually any hole configuration.In a preferred embodiment, the aiming guide system is used with a platehaving “combination holes.” A combination hole is any kind of hole inwhich there are multiple “hole positions” any one of which a surgeon canpenetrate or access. One example of a combination hole is an elongatedhole extending from an upper surface of a bone plate to a lower surfaceof a bone plate, and which has a threaded portion and a non-threadedportion. The threaded portion may extend over a range of greater thanhalf of the hole's circumference. The threaded portion of the hole maybe dimensioned and configured to engage a threaded head of a bone screw,and fix the bone screw at a predetermined angle with respect to the boneplate. The same type of screw or other types of screws, including screwsnot having threaded heads, may pass through the non-threaded portion ofa combination hole at any one of a number of angles.

The aiming guide system may have an aiming arm. In a first preferredembodiment, the arm extends substantially parallel to the bone plate inits lengthwise direction and has multiple bores. In a second preferredembodiment, the arm curves sideways, away from the bone plate. There maybe any number of bores in the aiming arm. The arrangement/pattern of thebores preferably matches or corresponds to the arrangement/pattern ofthe holes in the bone plate. Each bore is preferably aligned with thecenter of a corresponding bone plate hole (which may be in between therespective centers of each hole portion). In the second preferredembodiment in which the arm curves away from the bone plate, the boresmay be oriented at a non-perpendicular angle with respect to the planedefined by the top surface of the arm.

In a preferred embodiment, a tool guide may be positioned to runsubstantially straight between a bore of the aiming arm and acorresponding bone plate hole. In a preferred embodiment, the guide hasa head and a sleeve. A channel may extend through the head and sleeve.The channel may be centered with respect to the sleeve. The channel

and sleeve may be eccentric with respect to the head of the guide andthe bore of the arm (i.e., the channel and sleeve may not be positionedat the geometric center of the head and bore). This eccentricity serves,as described below, to align the guide sleeve with any one of multiplepositions within a given combination hole.

In a preferred embodiment, the tool guides have, at their heads, tworadially-extending, diametrically-opposed knobs. The knobs may mate withtwo corresponding diametrically opposed slots formed in the innersurface of each of the bores of aiming arm. Thus, when positioned in theslots, the knobs prevent a tool guide from rotational movement relativeto the bore and arm. The lock neutral guide may be placed within thebore in either of two possible positions. In one position, the eccentricchannel (and sleeve) is offset from center in one direction and istherefore aligned with one side of a combination hole. In the otherposition, 180 degrees rotated from the first position, the eccentricchannel (and sleeve) is offset from center in the opposite direction andis therefore aligned with the other side of the combination hole. Toaccomplish this, the knobs of the tool guide and the slots of the boresmay be dimensioned and configured such that the eccentricity of thesleeve and channel is offset from the center in a directioncorresponding with the direction of the array of hole positions within agiven plate hole. The surgeon thus has the option to align the sleeve,and hence the surgical tool being used, with either of the hole portionsof a combination hole.

In a preferred embodiment, a handle connects the aiming arm to the boneplate. The handle, at its lower end, may be secured to the bone plate. Alocking bolt may penetrate a substantially vertical chamber in thehandle and may secure the handle to the bone plate by being threadedinto a bone plate hole. The handle, at its upper end, may be secured tothe aiming arm. In a preferred embodiment, the handle is secured to theaiming arm by a coupling bolt. The coupling bolt may have a head and ashaft. The shaft may pass through a corresponding hole in the aiming armand mate with a hole located at the top surface of the head of theinterlocking bolt or at an upper surface of the handle

BRIEF DESCRIPTION OF THE DRAWINGS

These figures represent preferred embodiments of the aiming guidesystem. Those skilled in the art will recognize that numerous variationsand modifications may be made without departing from the scope of thepresent invention. Accordingly, it should be understood that thesefigures are not intended as limitations on the scope of the invention,which is defined only by the claims.

FIG. 1A is a plan view of a segment of a bone plate having combinationholes.

FIG. 1B is a schematic representation of a combination hole of the boneplate of FIG. 1A.

FIG. 2 is a perspective view of the assembled components of a firstembodiment of the aiming guide system of the present invention.

FIG. 3 is a side view of the aiming guide system of FIG. 2.

FIG. 4A is a side view of the interlocking bolt.

FIG. 4B is a cross-sectional view of the interlocking bolt of FIG. 4A.

FIG. 5A is a cross-sectional view of the handle of FIG. 2.

FIG. 5B is a top view of the handle of FIG. 2.

FIG. 6A is a side view of the locking nut.

FIG. 6B is a cross-sectional view of the locking nut of FIG. 6A.

FIG. 7 is a cross-sectional view of the coupling bolt.

FIG. 8A is a perspective view of the aiming arm of FIG. 2.

FIG. 8B is a bottom view of the aiming arm of FIG. 2.

FIG. 8C is a top view of the aiming arm of FIG. 2.

FIG. 9A is a side view of the lock neutral guide.

FIG. 9B is a side view, and partial cross-sectional, of the lock neutralguide of FIG. 9A, rotated 90 degrees.

FIG. 9C is a plan view of the lock neutral guide of FIG. 9A.

FIG. 10A is a side view of the thumb screw.

FIG. 10B is a cross-sectional view of the thumb screw of FIG. 10A.

FIG. 11 is a perspective view of the assembled components of a secondembodiment of the aiming guide system of the present invention.

FIG. 12A is a side view of the handle of FIG. 11.

FIG. 12B is a side view of the handle of FIG. 11, rotated 90° from theview of FIG. 12A.

FIG. 12C is a is a top view of the handle of FIG. 2.

FIG. 12D is a rear view of the assembled components of the aiming guidesystem of FIG. 11.

FIG. 13A is a side view of the arm of FIG. 11.

FIG. 13B is a side view, and partial cross-sectional view, of the arm ofFIG. 11.

FIG. 13C is a bottom view of the aiming arm of FIG. 11.

FIG. 13D is a top view of the aiming arm of FIG. 11.

FIG. 13E is a side cross-sectional side view of the arm of FIG. 11.

FIG. 13F is a cross-sectional view taken along axis 9A-9A of FIG. 13E.

FIGS. 14A and 14B are side views of two examples of a bone anchor thatmay be used with the aiming guide system.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The aiming guide system is described below with reference to theillustrated embodiments. Those skilled in the art will recognize thatnumerous variations and modifications may be made without departing fromthe scope of the present invention. Accordingly, it should be understoodthat the embodiments of the invention described above are not intendedas limitations on the scope of the invention, which is defined only bythe claims.

FIG. 1A illustrates one example of a section of a bone plate 90 havingone illustrative embodiment of holes 4 with which the aiming guidesystem is intended to be used. FIG. 1A illustrates a bone plate 90 whichincludes an upper surface 1, a bone contacting or lower surface 2 (notshown), and a plurality of combination holes 4 extending through theupper surface 1 and lower surface 2. The holes 4 may be elongated (e.g.,in a direction substantially aligned with a longitudinal axis of theplate) and may include a threaded portion 5 and a non-threaded portion6. The threaded portion 5 may extend over a range of greater than about180° with respect to a center point C1 of a first circular portion P1along which the threaded portion lies (discussed below). The threadedportion 5 of the hole 4 may be dimensioned and configured to engage athreaded head of a bone screw, and fix the bone screw at a predeterminedangle with respect to the bone plate. Preferably, the threaded portion 5extends through the full thickness of the bone plate, i.e., from theupper surface 1 to the lower surface 2, thus maximizing the stability ofthe bone screw to bone plate interface. The same type of screw, or othertypes of screws, including screws not having threaded heads, may passthrough the non-threaded portion 6 of a combination hole 4. Thespecifications of U.S. Pat. No. 6,669,701 and of U.S. Pat. No. 6,719,759disclose combination holes and are hereby incorporated by reference.

FIG. 1B is a schematic representation of the combination hole of FIG.1A. This combination hole may have a first circular portion P1 (alongwhich the threaded portion 5 may lie) and a second elongated portion P2(along which the non-threaded portion 6 may lie). The first circularportion P1 and the second elongated portion P2 overlap one another andare thus in communication with one another. The first circular portionP1 defines a first center point C1. The second elongated portion P2defines a second center point C2. In between these two points is acentral point C3.

Reference is now made to FIG. 2, which is a perspective view of theassembled components of a first preferred embodiment of the aiming guidesystem 20. The aiming guide system 20 provides alignment between asurgical tool (e.g., a drill bit 100, a trochar 101) and holes or holeportions in a bone plate. By use of the aiming guide system, a boneanchor (e.g., bone screws 150 and 151 shown in FIGS. 14A and 14B, a pin,a tack) can be properly aligned with the holes in the bone plate.

Though the aiming guide systems 20 and 220 are described in the contextof certain bone plates with certain hole arrangements and holeconfigurations, it should be noted that the aiming device may beutilized with any bone plate with virtually any hole distributionarrangement and virtually any hole configuration.

In this first preferred embodiment, the aiming guide system 20 includesa handle 30. The handle 30, at its lower end 34, may be attached to abone plate 90. The handle 30, at its upper end 35, may be attached to,or may be integral with, an aiming arm 10. The aiming arm 10 may extendsubstantially parallel to the bone plate 90 in the lengthwise directionand may have multiple bores 12. There may be any number of bores 12 inaiming arm 10. The arrangement/pattern of the bores 12 preferablymatches the arrangement/pattern of the holes in the bone plate 90. FIG.8C is a plan view of the top surface of aiming arm 10. The bores 12 maybe staggered to match a bone plate with a corresponding arrangement ofstaggered holes. Each bore 12 is preferably aligned with the centralpoint (C3 in FIGS. 1A and 1B) of a corresponding bone plate hole.

The aiming arm 10 is substantially straight along its longitudinal axisand the bores 12 may be substantially perpendicular to the top surface 8of the aiming arm 10. The top surface 8 of the aiming arm 10 is alsosubstantially flat and planar. As discussed more fully below inconnection with the description of another embodiment, the bores 12 mayextend through the arm 10 at a non-perpendicular angle with respect tothe top surface 8 of arm 10 and may be angled in one, two, or threeplanes. In addition, as discussed more fully below, the top surface 8 ofthe arm 10 may be curved and/or twisted along its longitudinal axis,curved and/or twisted along its width, or curved in both directions. Theaiming arm 10 also may bowed instead of flat and planar.

A tool guide, for example lock neutral guide 60, may be positioned in abore 12 of the aiming arm and may extend to a corresponding bone platehole 4. Thumb screws 15 may be inserted (e.g., threaded) into side holes14 in the aiming arm 10 in order to retain the guides 60 in the bores12. The guide 60 may be inserted into the bore 12 in one of at least twodifferent preset positions in order to align the guide 60 with aparticular hole portion of a bone plate hole 4. (The details of whichare illustrated in FIGS. 3, 8A-8C and 9A-9C and are discussed more fullybelow.) A tool (e.g., a drill bit, a trochar) may be received by theguide 60 and thereby aligned with a targeted hole portion of a givenhole 4.

Reference is now made to FIG. 3, which is a side view of the assembledcomponents of the first preferred embodiment of the present invention.The handle 30 may, at its lower end 34, be attached to the bone plate 90in any number of ways. In a preferred embodiment, the handle 30 isattached to the bone plate 90 by an interlocking bolt 40, which threadsinto a specific reference-point hole 91 in the bone plate 90. As shownin FIG. 4A, the interlocking bolt 40 may have a head 41, a shaft 42, andan externally-threaded end 43.

In a preferred embodiment, the lower end 34 of handle 30 is wider than,and straddles, the bone plate 90. As shown in FIGS. 5A and 5B, thehandle 30 may have a longitudinal bore or chamber 37 for insertion ofinterlocking bolt 40. As shown in FIG. 5A, the chamber 37 may extendfrom the upper surface to the lower surface of handle 30. After thehandle 30 is positioned on the bone plate 90, the interlocking bolt 40,may be dropped or rotated through the chamber 37 and threaded into hole91 in the bone plate 90, while the handle 30 is kept stationary. Forease of alignment between the interlocking bolt 40 and the referencehole 91 during insertion of the interlocking bolt 40, interlocking bolt40 may be cannulated to allow for the insertion of a guide wire throughthe interlocking bolt 40 and into hole 91 in the bone plate 90.

Before inserting the interlocking bolt 40 through the chamber 37 of thehandle 30, a locking nut 31 (shown in FIG. 6A) may be positioned on theshaft 42 of the interlocking bolt 40 and positioned to abut the head 41of the interlocking bolt 40. As shown in FIGS. 6B and 4B, the lockingnut 31 may have internal threads 38 to mate with an externally threadedportion 48 on the interlocking bolt 40. After the interlocking bolt 40has been inserted through the chamber 37 of the handle and threaded intothe hole 91 of the bone plate, the locking nut 31 may be rotated to takeup any slack in the connection between the handle 30 and the bone plate90. As shown in FIG. 6A, the locking nut 31 may knurled to aid theoperator in gripping the nut 31 when rotating it.

The nut 31 preferably has a diameter DN of about 1.0 cm to 1.8 cm. Theinterlocking bolt 40 preferably has a length LI of about 13 cm to 14 cmand a primary diameter DI of about 0.7 cm to about 0.9 cm. The chamber37 may have a diameter suitable to accommodate the interlocking bolt 40.

Handle 30, at its upper end 35, may be integral with, or attachable to,the aiming arm 10. The aiming arm 10 may be aligned with the handle 30in any number of ways as those skilled in the art will appreciate. In apreferred embodiment, pins 32 serve to align the handle 30 with theaiming arm 10. In one embodiment, the pins may be integral with thehandle 30 and mate with corresponding holes 17 in the arm 10, or viceversa. In another embodiment, unattached pins 32 may mate withcorresponding holes 36 and 17 in both the handle 30 and arm 10,respectively. (See FIG. 8A.) Pin holes 36 in the top surface of handle30 are shown in FIG. 5B. Pin holes 17 in the bottom surface of aimingarm 10 are shown in FIG. 8B.

In a preferred embodiment, the handle 30 is removably attachable to theaiming arm 10. The handle 30 may be secured to the aiming arm 10 in anynumber of ways. One end of the aiming arm may be positioned over the topsurface of the handle. There may be a space 87 (shown in FIG. 8B) in thebottom surface of aiming arm 10 to provide clearance for the head 41 ofthe interlocking bolt 40. In a preferred embodiment, the handle 30 issecured to the aiming arm 10 by a coupling bolt 33. As shown in FIG. 7,coupling bolt 33 may have a head 18 and a shaft 19. The shaft 19 maypass through a corresponding hole 16 (shown in FIG. 8B) in the aimingarm 10 and mate with a hole 44 located at the top surface of the head 41of the interlocking bolt 40. Shaft 19 may have external threads 85(shown in FIG. 7) to mate with corresponding internal threads 86(identified in FIG. 8B) of the hole 16 of aiming arm 10 and to mate withcorresponding internal threads 46 (shown in FIG. 4B) on the innersurface of hole 44 of the interlocking bolt 40.

Shaft 19 preferably has a length LC of about 1.1 cm to 1.7 cm and adiameter DC of about 0.4 cm to 0.6 cm. Handle 30 preferably has a heightHH of about 10 cm to 14 cm.

FIGS. 8A (a perspective view of the aiming arm 10) and 8C (a top view ofthe aiming arm 10) illustrate bores 12, each having two diametricallyopposed slots 13 formed in their inner surfaces 49. Slots 13 preferablydo not extend from the top surface 8 to the bottom surface 7 of theaiming arm 10. Reference is made to FIG. 8B, which is a bottom view ofthe arm 10. In one embodiment in which the arm 10 has seven bores 12,the arm 10 preferably has a length LA of about 14 cm to about 19 cm anda width WA of about 2.5 cm to about 3.5 cm. Bore 12 preferably has adiameter DB of about 1.3 cm to about 1.9 cm. The distance b betweenadjacent bore 12 centers is preferably about 1.5 cm to about 2.1 cm.Depending upon the size of the bone plate and the arrangement of thebone plate holes, the length LA, width WA, distance b between adjacentbore holes, and the orientation of the bores 12 can be varied.

As shown in FIGS. 9A and 9B, the lock neutral guide 60 may have a head61 and a sleeve 62. A channel 65 may extend through the head 61 andsleeve 62. The channel 65 and sleeve 62 may be eccentric with respect tothe head 61 and bore 12 (i.e., the channel and sleeve may not bepositioned at the geometric center of the head 61 and bore 12). As shownin FIG. 9A, the central longitudinal axis B-B of the sleeve 62 may beoffset from the central longitudinal axis A-A of the head 61. In apreferred embodiment, the distance d between axis A-A and axis B-B ispreferably about 0.16 cm to about 0.20 cm. It will be appreciated thatthis eccentricity will serve to align the guide sleeve 62 with differentportions of a combination hole (e.g., combination hole 4).

The heads 61 of the lock neutral guides 60 may have a first portion 70with diameter D1 and a second portion 71 with diameter D2, the diameterD2 being greater than the diameter D1. The diameter D2 may also begreater than the Diameter D3 (shown in FIG. 9A) of the bore. Diameter D1may be slightly smaller than D3 such that there is a slip fit betweenthe first portion 70 of head 61 of guide 60 and the bore 12. The outersurface of the first portion 70 of guide 60 may contact the innersurface of the bore 12, but the “fit” between the two may besufficiently loose to allow for manual movement of the guide 60 withrespect to the bore 12. And when, as in this embodiment, diameter D2 ofthe second portion 71 is greater than diameter D3 of the bore, thesecond portion 71 will not fit within the bore 12 and instead will, atthe appropriate point, stop the advancement of the guide 60 through thebore 12. Diameter D1 is preferably about 1.3 cm to about 1.8 cm.Diameter D2 is preferably about 1.7 cm to about 2.1 cm. Diameter D3 ispreferably about 1.3 cm to about 1.9 cm.

In a preferred embodiment, as shown in FIG. 9B, the lock neutral guides60 may have, at the circumferential outer surface of their heads 61, tworadially-extending, diametrically-opposed knobs 63. Knobs 63 may matewith the two corresponding diametrically opposed slots 13 (shown in FIG.8A) formed in the inner surface of the bores 12 of aiming arm 10. Thus,when positioned in slots 13, the knobs 63 prevent a lock neutral guide60 from rotational movement relative to the bore 12 and arm 10. Lockneutral guide 60, in the embodiment of FIGS. 2 and 11, may be positionedwithin the bore 12 in either of two possible predetermined positions. Inone position, the eccentric channel 65 and sleeve 62 is offset in onedirection and is therefore aligned with one side of the combinationhole. In the other position, 180 degrees rotated from the firstposition, the eccentric channel 65 (and sleeve 62) is offset in theopposite direction and is therefore aligned with the other side of thecombination hole. To accomplish this, the knobs 63 of the tool guide andthe slots 13 of the bores 12 may be dimensioned and configured such thatthe eccentricity of the sleeve 62 and channel 65 is offset from thecenter (of the bore 3 and head 61) in a direction and distancecorresponding to the dimensions of the given plate hole. The surgeonthus has the option to align the sleeve 62, and hence the surgical tool,with either of the hole portions of a combination hole.

Shaft 62 of guide 60 preferably has a length LS of about 11 cm to about12 cm and a diameter DS of about 0.7 cm to about 1.1 cm. Head 61preferably has a length LH of about 3.0 cm to about 3.5 cm. Knobs 63extend radially beyond the outer circumference of the head 61 preferablyby about 0.20 cm to about 0.22 cm.

In one embodiment, the heads 62 of the lock neutral guides 60 may begenerally circular. In a preferred embodiment, as shown in FIG. 9C, thesecond portion 71 of the head 62 may be generally circular, but have twosegments of the circumference interrupted by two flat portions 74.Second portion 71 of head 62 may therefore be wide enough to preventover-insertion of the guide 60 into the bore 12, but narrow enough inthe direction facing other bores 12 to prevent heads 62 of guides 60placed in closely adjacent bores from obstructing each other.

Any configuration or relationship between the lock neutral guide 60 andthe bore 12 may be established and used to limit the guide 60 to presetpositions within a bore 12 and to prevent relative rotational movement.For example, the mating arrangement could be reversed: the knobs couldextend radially inward from the bore 12 and mate with slots formed onthe outside of the guide 60. Also for example, instead of knobs 63, theguide 60 could have more sizeable (e.g. wider and longer) radiallyextending protrusions, to mate with corresponding recesses on theinternal surface of the bore 12. In addition, the circumferential shapeof head 62 and bores 12 could be keys so as to limit the position of thesleeve within the bore to one, two, or more predetermined positions sothat the channel 65 will align with different areas of the bone platehole depending upon the position of the head 62 with respect to the bore12.

It will be appreciated that the eccentric channel 65 and sleeve 62 maybe used with aiming arms having properties, features, and aconfiguration that are different from the afore-described aiming arm 10.For example, the bores 12 of the aiming arm 10 may be perfectly alignedwith the center (e.g., center C1 or C2 shown in FIGS. 1A and 1B) of oneof multiple hole positions of a combination hole (rather than with thecentral point, e.g., center C3 shown in FIGS. 1A and 1B of a combinationhole). The bore 12 may receive a tool guide in only one position (ratherthan in two positions). Thus, it will be appreciated that a guide with acenter sleeve (rather than one with an eccentric sleeve) could be usedto align a tool with the portion of a combination hole that the bore isaligned with. If a surgeon wishes to penetrate or access another portionof a hole, a guide with a suitably eccentric sleeve may be used. Thedegree of eccentricity, it will be appreciated, would be greater in thisembodiment than in the aforementioned embodiments. Thus, in oneembodiment, a surgeon can access different portions of a hole,preferably an elongated or overlapping hole, by selecting theappropriate sleeve (rather than by using one sleeve and selecting theappropriate orientation). The one-sleeve system, however, is preferred.

Reference is now made to FIGS. 10A and 10B. FIG. 10A is a side view ofthe thumb screw 15. In this embodiment, thumb screw 15 has a head 80 anda penetrating shaft 81. Thumb screws 15 penetrate through side holes 14of aiming arm 10 and into grooves 79 formed in the outer surface ofheads 61 of lock neutral guides 60 in order to retain guides 60 in thebores 12. In a preferred embodiment, shaft 81 has external threads 88(shown in FIG. 10B) which mate with internal threads (not shown) of sideholes 14 of aiming arm 10. Shaft 81 preferably has a length LT of about0.8 cm to about 1.2 cm and a diameter DT of about 0.19 cm to about 0.25cm.

Another embodiment, having an arm and a handle with characteristicsdifferent from those of the first embodiment, is illustrated in FIG. 11,which is a perspective view of the assembled components of an aimingguide system 220. The embodiment shown in FIG. 11 is intended for usewith a bone plate which, for example, along its shaft, has a twist. Theplate may be a proximal tibia plate, but could be a bone plate for otherbones as well, including plates for other long bones. The plate 290 mayhave a head 294 and a shaft 298. The plate 290 may have holes which, dueto the twist of the shaft 298, may be angled in one, two, or threeplanes. Moving away from the head 294, most or all of the plate holes onthe shaft 298 may be oriented at progressively increasing angles (i.e.,in FIG. 11 each hole may be oriented at an angle greater than the holeto its left, with the hole at the free end of the shaft 298, the endopposite the head 294, having the greatest angle as a result of thegreater twist of the free end of the shaft 298).

Because the holes of the plate 290 are, unlike the holes of the plate90, oriented at different angles, the aiming arm 10 may not becompatible with the plate 290 (i.e., the lock neutral guides would notbe positioned at the plate holes at the proper insertion angles). Theaiming arm 210, however, is specifically designed to complement a platehaving a twist, a bend, or holes oriented at different angles. Theaiming arm 210, unlike the aiming arm 10, may extend and besubstantially non-parallel to the bone plate in a lengthwise direction.As shown in FIG. 13D (which is a top view of aiming arm 210), aiming arm210 may be curved sideways. In one non-limiting illustrative embodiment,the radius of curvature R of arm 210 may be about 140 cm to about 170cm. The curvature of the aiming arm 210 places the bores 212 laterallyaway from the plate holes. As the aiming arm 210 extends in a thegeneral direction of the length of the bone plate 290 and away from thehandle 230, most of the bores 212 are distanced progressively furtheraway from the corresponding holes in the plate 290. The effect oflocating the bores 212 away from the plate holes is to accommodate thetwist in the bone plate which orients the axes of the bone plate holesat an angle relative to the top surface 208 and the bottom surface 207of the aiming arm 210.

The arm bores 212 may be angled in a direction and at a degree dictatedby and matching the angle of the corresponding hole. Thus, as the plateholes are biased from the head end 55 of the shaft 298 to the free end56 of the shaft 298 at progressively increasing angles, so too may thebores 212 be oriented from the handle-end 58 of the arm 210 to the freeend 59 of the arm 210 at progressively increasing angles. The arm bores212 may have an angled countersink region 57 to accommodate the heads oflock neutral guides 60. Without the countersink region 57, there is onlyminimal contact and hence minimal stability between the heads of thelock neutral guides 60 and the aiming arm 210. Thus, the countersinkregion 57, which may be formed of one or more cutouts or indentationsaround at least a portion of the bores 212 near the upper surface 208 ofthe aiming arm 210, provides for additional contact between the heads oflock neutral guides 60 and the aiming arm 210.

In one embodiment, each of the bores 212 may be oriented at an anglerelative to the aiming arm 210 in two planes. In a first plane (definedby the cross section of the arm 210 shown in FIG. 13E), the bores 212may all be biased to the same degree, creating an angle α, as shown inFIG. 13E. In one embodiment the bores may be oriented in a directiontoward the free end of the arm 210 by about 0.1° to about 1.5°, creatingan angle α of about 90.1° to about 91.5°. It should be appreciated thatthe bores 212 can be oriented in the plane shown in FIG. 13E by a largeror smaller angle and in a different direction. It can further beappreciated that the angle of the orientation in this first plane canchange for each bore 212. The bores 212 may be oriented in a secondplane through the aiming arm. The bores 212 may be oriented in adirection toward the bone plate at varying degrees denoted by angle γ inFIG. 13F (which is a cross-sectional view of the arm 210 taken along theaxis 9A-9A of FIG. 13E). The second plane in this illustrativeembodiment is defined by the plane perpendicular to the first plane andin the plane defined by each pair of slots 213. In one embodiment, angleγ may vary from about 0° to about 5°. In one embodiment, the bore 212′(shown in FIGS. 13E and 13F) located nearest to the handle 230 may haveno angle (i.e., angle γ of 0°), and the bore 212″ (noted at crosssection 9A-9A and shown in FIGS. 13E and 13F) located at the oppositeand free end of arm 210 may have an angle γ of about 5°. The bores 212in between the two end bores 212′ and 212″ may each have differentangles γ between about 0° and about 5°, gradually increasing from about0° to about 5° along the aiming arm 210 from the end bore 212′ to 212″.In other embodiments, the respective angles γ may be different from theaforementioned angles γ, in range, in progression/assortment, and/or indirection.

In an illustrative embodiment shown in FIGS. 13A-13F, the arm 210 hasnine bores 212, and the arm 210 preferably has a length LA2 of about 21cm to about 27 cm and a width WA2 of about 3.0 cm to about 3.6 cm. Inone embodiment, each bore 212 has a diameter DB2 of about 2.0 to about2.4 cm. In one embodiment, the distance b2 between adjacent bore 212centers may be about 1.5 to about 2.1 cm.

In an alternative embodiment, an aiming arm having a twist and curvecorresponding to the twist and curve of a bone plate, and havingstraight bores, may be used to accommodate a bone plate having a twist.

Reference is now made to FIGS. 12A, 12B, and 12C, which are side and topviews of a handle 230 for the aiming guide system 220. As shown in FIG.12A, the handle 230 may have a longitudinal bore or chamber 237 forinsertion of an interlocking bolt, which may secure the handle 230 tothe bone plate 290 in similar fashion to how the interlocking bolt 40secures the handle 30 to the plate 90, as described above. Theinterlocking bolt of this embodiment may be similar in form and functionto the interlocking bolt 40. The interlocking bolt of this embodimentmay have similar dimensions and measurements to those of theinterlocking bolt 40 or may be varied as necessary.

The connection between the arm 210 and the handle 230 will now bedescribed. As shown in FIG. 12A, the handle may have a platform 239 onwhich the end portion 211 (shown in FIG. 13A) of arm 210 sits, and mayhave an upward projection 238, which may be received in a correspondinghole 287 (shown in FIGS. 13B and 13E) on the end portion 211 of arm 210.Further aligning the handle 230 and arm portion 210, are pins (like pins32) which may be received by holes 236 (shown in FIG. 12C) in the handle230 and by holes 217 (shown in FIGS. 13C and 13E) of the aiming arm 210.To secure the arm 210 to the handle 230, a coupling bolt 33 may be used.The coupling bolt 33 may have a shaft 19 which may pass through a hole216 (shown in FIGS. 13B, 13D, and 13E) in the aiming arm 210 and matewith a hole 233 on the upper surface of the projection 238 of the handle230. Shaft 19 of coupling bolt 33 may have external threads 85 (shown inFIG. 7) to mate with corresponding internal threads 286 (identified inFIG. 13D) of the hole 216 of aiming arm 210 and with correspondinginternal threads 246 on the inner surface of hole 233 on the platform239 of the handle 230.

In an optional embodiment, the handle 230, unlike the handle 30, mayextend from the plate at a non-perpendicular angle δ with respect to theplane defined by the upper surface of the head 294 of the plate 290. Thehandle 230 may extend at a non-perpendicular angle, for example, inorder to provide space for the use of additional instrumentation to beused to operate the system. As a non-limiting example, handle 230 mayextend from the plate 290 at an angle δ from about 10° to about 20° asshown in FIG. 12D. The angle δ may be determined by the orientation ofthe reference hole in which the interlocking bolt is inserted. Thehandle 230 preferably, in a non-limiting example, has a height HH2 ofabout 10 cm to about 14 cm, although other dimensions are probable.

The lock neutral guides 60 may be used with aiming arm 210 as they areused with aiming arm 10. Bores 212 have diametrically opposed slots 213on their inner surfaces. To secure the guides 60 in the bores 212, thumbscrews 15 may penetrate side holes 214 of aiming arm 210 and mayotherwise be used as described above in connection with the firstpreferred embodiment.

While the present invention has been described with reference to thepreferred embodiments, those skilled in the art will recognize thatnumerous variations and modifications may be made without departing fromthe scope of the present invention. As a non-limiting illustrativeexample, in order to obtain the proper alignment between the guidesleeves and the desired bone plate, the bores through the aiming arm canbe arranged at different angles—and in one, two, or three planes—throughthe aiming arm and the aiming arm can be curved, twisted, or bent inone, two, or three planes which will all be a matter of design choice.Accordingly, it should be understood that the embodiments of theinvention described above are not intended as limitations on the scopeof the invention, which is defined only by the following claims.

1. A device for aligning at least one surgical tool with a hole in abone plate extending along a longitudinal axis, the device comprising: ahandle portion including a coupling structure for coupling the handleportion to a bone plate in a desired orientation relative thereto; anarm portion extending along an arm portion longitudinal axis betweenfirst and second ends, the arm portion being coupleable to the handleportion in a desired orientation relative thereto, wherein, when coupledto the handle portion in the desired orientation, the arm portionlongitudinal axis extends transverse to a longitudinal axis of thehandle portion, the arm portion defining top and bottom surfaces andincluding a first bore extending through the arm portion from the topsurface to the bottom surface, wherein an axis defined by the first boreis transverse to the arm portion longitudinal axis; and a first toolguide extending along a first tool guide longitudinal axis from thefirst bore of the arm portion toward a bone plate coupled to the handleportion, the first tool guide defining a first channel, wherein thefirst bore and the first tool guide are configured and adapted to permitthe first tool guide to be received in the first bore in a selected oneof two different preset positions, each of the selected preset positionsoffsets the first tool guide longitudinal axis from a center of thefirst bore in a different direction.
 2. The device of claim 1, wherein alongitudinal axis of the first bore is offset from the arm portionlongitudinal axis.
 3. The device of claim 1, wherein the first boreincludes two diametrically opposed slots extending along at least aportion of a length of the first bore, the first tool guide havingdiametrically opposed knobs extending outwardly from the first toolguide, the slots configured and dimensioned to mate with the knobs toalign the first tool guide in the first bore.
 4. The device of claim 3,wherein a first one of the preset positions is located 180 degrees froma second one of the preset positions.
 5. The device of claim 3, whereinthe first tool guide has a head and a sleeve portion, the first channelbeing centered with respect to the sleeve portion, and the sleeveportion being eccentric with respect to the head.
 6. The device of claim5, wherein, in a first one of the preset positions, the eccentric sleeveportion of the first tool guide and the first channel are aligned with afirst portion of a hole in a bone plate and, in a second one of thepreset positions, the eccentric sleeve portion and the first channel arealigned with a second portion of a hole in a bone plate.
 7. The deviceof claim 5, wherein a central longitudinal axis of the sleeve portion ofthe first tool guide is offset from a central longitudinal axis of thehead by a distance of approximately 0.16 cm to approximately 0.20 cm. 8.The device of claim 1, wherein the first bore is aligned with a centralpoint of a bone plate hole.
 9. The device of claim 1, wherein the firstbore is aligned with a center of one portion of a bone plate hole. 10.The device of claim 1, wherein an arrangement of bores along the armportion substantially matches arrangement of holes along at least aportion of a bone plate to be coupled to the handle.
 11. The device ofclaim 1, wherein the first bore is oriented perpendicular to the topsurface of the arm portion.
 12. The device of claim 1, wherein the atleast one first bore is oriented at a non-perpendicular angle withrespect to the top surface of the arm portion.
 13. The device of claim12, wherein the first bore is angled in one of one, two, or three planeswith respect to the top surface of the arm portion.
 14. The device ofclaim 13, wherein the angle formed in each plane is approximately 0° to5°.
 15. The device of claim 1, wherein the first tool guide is at leastone of the group comprising a drill bit, a trochar, and a bone tap. 16.The device of claim 1, wherein the handle portion has a chamber, andfurther comprising an interlocking bolt configured to extend though thechamber and into a hole in a bone plate to be coupled thereto.
 17. Theof claim 16, wherein the chamber extends the length of the handleportion.
 18. The device of claim 16, wherein the interlocking bolt has ahead, shaft, and end portion, the end portion having threads forengaging a hole in a bone plate.
 19. The device of claim 18, wherein aninternally-threaded locking nut, configured and dimensioned to mate withexternal threads on the interlocking bolt, is positioned between thehead of the interlocking bolt and the top surface of the handle portion.20. The device of claim 1, wherein the arm portion is aligned with thehandle portion by mating pins configured and dimensioned to mate withholes in the bottom surface of the arm portion and holes in the topsurface of the handle portion.
 21. The device of claim 1, wherein thehandle portion is secured to the arm portion by a coupling bolt.
 22. Thedevice of claim 1, further comprising a thumb screw threaded into acorresponding recess in the side of the arm portion to retain the firsttool guide in the first bore.
 23. The device of claim 1, whereinrotating the first tool guide from a first preset position to a secondpreset position moves the channel relative to the arm portionlongitudinal axis.
 24. The device of claim 1, wherein a first one of thepreset positions corresponds to a first configuration in which a distalend of the first tool guide is in alignment with a first portion of afirst combination hole of the bone plate, and a second one of the presetpositions corresponds to second configuration in which the distal end ofthe first tool guide aligns with a second portion of the firstcombination hole.
 25. An device for aligning at least one surgical toolwith a hole in a bone plate extending along a longitudinal axis, thedevice comprising: a handle portion including a coupling structure forcoupling the handle portion to a bone plate in a desired orientationrelative thereto; an arm portion extending along an arm portionlongitudinal axis between first and second ends, the arm portion beingcoupleable to the handle portion in a desired orientation relativethereto, wherein, when coupled to the handle portion in the desiredorientation, the arm portion longitudinal axis extends transverse to alongitudinal axis of the handle portion, the arm portion defining topand bottom surfaces, and including a first bore extending through thearm portion from the top surface to the bottom surface, wherein an axisdefined by the first bore is transverse to the arm portion longitudinalaxis; and a first tool guide extending along a first tool guidelongitudinal axis from the first bore of the arm portion toward a boneplate coupled to the handle portion, the first tool guide including asleeve portion defining a channel, the tool guide having a head, thehead being positioned at least partially within the first bore, thechannel being centered with respect to the sleeve portion, and thesleeve portion and channel being eccentric with respect to the head,wherein the first bore and the first tool guide are configured andadapted to permit the first tool guide to be received in the first borein a selected one of two different preset positions, each of theselected preset positions offsets the first tool guide longitudinal axisfrom a center of the first bore in a different direction.
 26. The deviceof claim 25, wherein the first one bore is offset from the longitudinalaxis of the arm portion.
 27. The device of claim 25, wherein the firstbore includes two diametrically opposed slots extending along at least aportion of a length of the first bore, the slots configured anddimensioned to mate with diametrically opposed knobs extending radiallyoutward from the first tool guide.
 28. The device of claim 27, wherein afirst one of the preset positions is located 180 degrees from a secondpreset position.
 29. The device of claim 27, wherein, in a first one ofthe preset positions, the eccentric sleeve portion of the first toolguide and the channel are aligned with a first portion of a hole in abone plate coupled to the handle and, in a second one of the presetpositions, the eccentric sleeve portion and channel are aligned with asecond portion of a hole in a bone plate coupled to the handle.
 30. Thedevice of claim 25, wherein the first bore is aligned with a centralpoint of a hole in a bone plate.
 31. The device of claim 25, wherein thefirst bore is aligned with a center of one portion of a hole in a boneplate.
 32. The device of claim 25, wherein an arrangement of bores alongthe arm portion substantially matches an arrangement of holes along atleast a portion of a bone plate to be coupled to the handle.
 33. Thedevice of claim 25, wherein the first bore is oriented perpendicular tothe top surface of the arm portion.
 34. The device of claim 25, whereinthe first bore is oriented at a non-perpendicular angle with respect tothe top surface of the arm portion.
 35. The device of claim 34, whereinthe first bore is angled in one of one, two, or three planes withrespect to the top surface of the arm portion.
 36. The device of claim35, wherein the angle formed in each plane is approximately 0° toapproximately 5°.
 37. The device of claim 25, wherein the handle portionis aligned with the arm portion by mating pins with holes at the bottomsurface of arm portion and with corresponding holes at the top surfaceof the handle portion.
 38. The device of claim 25, wherein the handleportion is secured to the arm portion by a coupling bolt.
 39. The deviceof claim 25, wherein the handle portion has a chamber through its lengthand an interlocking bolt configured to extends through the chamber andinto a hole in a bone plate to be coupled thereto.
 40. The device ofclaim 39, wherein the interlocking bolt has a head, shaft, and endportion configured to be threaded into a hole in a bone plate to becoupled to the handle.
 41. The device of claim 40, wherein theconnection between the interlocking bolt and a bone plate is tightenedwith a locking nut positioned between the head of the interlocking boltand the top surface of the handle portion.
 42. The device of claim 25,further comprising a thumb screw threaded into a corresponding recess inthe side of the arm portion to retain the tool guide in the bore. 43.The device of claim 25, wherein a central longitudinal axis of thesleeve portion is offset from a central longitudinal axis of the head aby distance of between approximately 0.16 cm and approximately 0.20 cm.44. The device of claim 25, wherein rotating the first tool guide from afirst preset position to a second preset position moves the channelrelative to arm portion longitudinal axis.